In the eukaryotic cell, the cytoskeleton is made up primarily of actin filaments, which are about 7 nanometers (nm) in diameter; of intermediate filaments, about 8-11 nm in diameter; and microtubules, which are more complex structures.

The platelet cytoskeleton must undergo complicated rearrangements that are responsible for a repertoire of changes in cell shape during a blood clotting reaction (Figure 18-8).

A critical difference between the erythrocyte and platelet cytoskeletons is the presence in the platelet of the second network of actin filaments, which are organized by filamin cross-links into a three-dimensional gel (see Figure 18-5b).

We believe that the cytoskeleton is one of a few biological areas with broad potential for drug discovery and development and has been scientifically and commercially validated in a wide variety of human diseases.

For example, the cytoskeleton plays a fundamental role in the cell proliferation process, and cancer is a disease of unregulated cell proliferation.

As another example, the cytoskeleton plays a fundamental role in cardiac muscle contraction and has been linked to the origins of congestive heart failure, a disease of impaired cardiac function.

www.cytokinetics.com /cyto/overview_cytoskeleton (191 words)

Plant Cell Cytoskeleton(Site not responding. Last check: 2007-10-19)

The cytoskeleton is a set of small filaments that is found in the cytoplasm of eukaryotic cells.

For the process of phagocytosis, the cytoskeleton helps the cell move liquid into the cell, and in the process of pinocytosis, the cytoskeleton helps the cell move large particles into the cell.

Furthermore, the actincytoskeleton enables adherent cells, such as fibroblasts, to form contacts (called focal adhesions) with its “substratum” (i.e., extracellular matrix proteins or plastic in a petri dish).

Although the roles of many of these effectors in regulating changes in the actincytoskeleton and gene transcription remain unclear, it is evident that Rac and Cdc42 control proteins with highly divergent activities (i.e., lipid kinases, protein kinases, adaptor proteins).

A three-dimensional network of fibers, composed of filamentous protein, which runs throughout the matrix of living cells, providing a framework for organelles, anchoring the cell membrane, and providing a suitable surface for chemical reactions to take place.

The cytoskeleton also provides the cell with motility – the ability of the entire cell to move around and for material to be moved within the cell.

Although the term “cytoskeleton” is well used and accepted, it unfortunately gives an impression of a rather static entity.

A unique feature of the trypanosome cytoskeleton is that upon membrane extraction with non-ionic detergents (e.g.

The extracted cytoskeletons can be separated from the detergent insoluble material by centrifugation.

The Trypanosome cytoskeleton consists primarily of microtubule-based structures, which can be both physically and conceptually divided into two fractions, "the subpellicular fraction" and "the flagellar fraction".

Cytoskeleton is organized in a spatially and temporally specific manner.

In this study, we demonstrated that a mutant in which the normal myosin II was replaced with a truncated form, heavy meromyosin (hmm), is defective in cytokenesis and mobility of surface receptors (Con-A capping), and myosin II is localized only diffusely in the cytoplasm (left).

This finding helped establishing a then new idea that actincytoskeleton is the key framework, which is associated with various binding proteins including myosin II in spatially unique manners.

The cytoskeleton is a diverse, multi-protein framework that plays a fundamental role in many cellular activities including mitosis, cell division, intracellular transport, cell motility, muscle contraction, and the regulation of cell polarity and organization.

Furthermore, cytoskeletal proteins have been implicated in the etiology or pathogenesis of a wide variety of diseases including cancer, cardiovascular disease, inflammatory disease, fungal, bacterial and viral infections, and neurodegenerative disease.

In many ways, the cytoskeletal framework can be likened to a highly organized city plan, with highways, motor cars, construction crews and street signs, whose structure and function is directly observable in the living cell.

To examine these questions, this volume describes the properties of the individual proteins of the cytoskeleton and their assembly into the filamentous structures that are responsible for the remarkably stiff consistency of cytoplasm.

Cytoskeletons give cells their shape, help cells move, and hold the nucleus in place.

In either case, they are responding to a control system in which the shape-shifting cytoskeleton serves as a switching mechanism.

Cytoskeleton Tutorial -- (University of Arizona) The cytoskeleton is both a muscle and a skeleton, and is responsible for cell movement, cytokinesis, and the organization of the organelles within the cell.